Australian Tropical Rainforest Plants - Online edition

Croton insularis Baill.


Shrub (woody or herbaceous, 1-6 m tall)
Tree
Click/tap on images to enlarge
Male flowers [not vouchered]. © G. Sankowsky
Leaves and Flowers. © CSIRO
Leaves and Flowers. © CSIRO
Scale bar 10mm. © CSIRO
10th leaf stage. © CSIRO
Cotyledon stage, epigeal germination. © CSIRO
Family

Baillon, H.E. (1978) Adansonia 1: 217. Type: Pancher, 1er env., n. 360 N.-Caled., in collibus. Vieillard, 1er env., N.-Caled. Herb. propr. (1855-60), n. 1136, 1137, 1138, Balade.

Common name

White Croton; Cascarilla Bark; Native Cascarilla Bark; Queensland Cascarilla; Queensland Cascarilla Bark; Silver Croton

Stem

Blaze odour fragrant and spicy. White granular stripes normally visible in the outer blaze.

Leaves

Leaf blades about 5-8 x 2.5-4 cm, +/- white on the underside but peppered with numerous small brown scales. Oil dots visible with a lens. Two raised glands present at the base of the leaf blade at its junction with the petiole.

Flowers

Inflorescence and calyx clothed in silvery or coppery lepidote scales. Male flowers: Flowers about 3 mm diam. with about 11 or 12 stamens. Female flowers: Flowers about 3 mm diam. Ovary densely clothed in silvery or coppery lepidote scales in the female flowers.

Fruit

Capsules about 5-7 mm diam., clothed in silvery or coppery lepidote scales.

Seedlings

Cotyledons elliptic, about 8-10 mm long. At the tenth leaf stage: leaf blade white on underside; both the upper and lower surfaces of the leaf blade, young shoots, and stem clothed in flat scales each with a central red gland; 1 or 2 peg-like glands visible near the junction of the petiole and the leaf blade; oil dots visible with a lens. Seed germination time 13 days.

Distribution and Ecology

Occurs in CYP, NEQ, CEQ and southwards as far as coastal central New South Wales. Altitudinal range in NEQ from 400-1100 m. In NEQ grows in the drier rain forests, often associated with Kauri Pine (Agathis robusta). Also occurs in Vanuatu and New Caledonia.

Natural History & Notes

When injured, the bark gives off a very pleasant aromatic odour resembling that of cascarilla, a West Indian species of Croton whose bark was once was as a tonic. The Australian species has been suggested as a substitute for the West Indian material but there seems to be no record of its being used here. Cribb (1981).

Synonyms
Croton insularis Baill. var. insularis, Prodromus 15(2.: 527(1866). Croton insularis var. genuinus Mull.Arg., Prodromus 15(2.: 527(1866). Oxydectes insularis (Baill.) Kuntze, Rev. Gen. Pl. 2: 612(1891).
RFK Code
143
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